[PATCH 4/8] firmware: qcom: scm: Add support for ARM64 SoCs
Andy Gross
andy.gross at linaro.org
Fri Apr 22 15:17:08 PDT 2016
From: Kumar Gala <galak at codeaurora.org>
Add an implementation of the SCM interface that works on ARM64 SoCs. This
is used by things like determine if we have HDCP support or not on the
system.
Signed-off-by: Kumar Gala <galak at codeaurora.org>
Signed-off-by: Andy Gross <andy.gross at linaro.org>
---
drivers/firmware/qcom_scm-32.c | 4 +
drivers/firmware/qcom_scm-64.c | 194 ++++++++++++++++++++++++++++++++++++++++-
drivers/firmware/qcom_scm.c | 7 ++
drivers/firmware/qcom_scm.h | 4 +
4 files changed, 207 insertions(+), 2 deletions(-)
diff --git a/drivers/firmware/qcom_scm-32.c b/drivers/firmware/qcom_scm-32.c
index 9e3dc2f..0d2a3f8 100644
--- a/drivers/firmware/qcom_scm-32.c
+++ b/drivers/firmware/qcom_scm-32.c
@@ -482,3 +482,7 @@ int __qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt, u32 *resp)
return qcom_scm_call(QCOM_SCM_SVC_HDCP, QCOM_SCM_CMD_HDCP,
req, req_cnt * sizeof(*req), resp, sizeof(*resp));
}
+
+void __qcom_scm_init(void)
+{
+}
diff --git a/drivers/firmware/qcom_scm-64.c b/drivers/firmware/qcom_scm-64.c
index bb6555f..86bec08 100644
--- a/drivers/firmware/qcom_scm-64.c
+++ b/drivers/firmware/qcom_scm-64.c
@@ -13,6 +13,142 @@
#include <linux/io.h>
#include <linux/errno.h>
#include <linux/qcom_scm.h>
+#include <linux/cpumask.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/qcom_scm.h>
+#include <linux/arm-smccc.h>
+
+#include <asm/cacheflush.h>
+#include <asm/compiler.h>
+#include <asm/smp_plat.h>
+
+#include "qcom_scm.h"
+
+#define QCOM_SCM_FNID(s, c) ((((s) & 0xFF) << 8) | ((c) & 0xFF))
+
+#define MAX_QCOM_SCM_ARGS 10
+#define MAX_QCOM_SCM_RETS 3
+
+#define QCOM_SCM_ARGS_IMPL(num, a, b, c, d, e, f, g, h, i, j, ...) (\
+ (((a) & 0xff) << 4) | \
+ (((b) & 0xff) << 6) | \
+ (((c) & 0xff) << 8) | \
+ (((d) & 0xff) << 10) | \
+ (((e) & 0xff) << 12) | \
+ (((f) & 0xff) << 14) | \
+ (((g) & 0xff) << 16) | \
+ (((h) & 0xff) << 18) | \
+ (((i) & 0xff) << 20) | \
+ (((j) & 0xff) << 22) | \
+ (num & 0xffff))
+
+#define QCOM_SCM_ARGS(...) QCOM_SCM_ARGS_IMPL(__VA_ARGS__, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)
+
+/**
+ * struct qcom_scm_desc
+ * @arginfo: Metadata describing the arguments in args[]
+ * @args: The array of arguments for the secure syscall
+ * @res: The values returned by the secure syscall
+ * @extra_args_virt: The buffer containing extra arguments
+ (that don't fit in available registers)
+ * @extra_args_phys: The physical address of the extra arguments
+ */
+struct qcom_scm_desc {
+ u32 arginfo;
+ u64 args[MAX_QCOM_SCM_ARGS];
+ struct arm_smccc_res res;
+
+ /* private */
+ void *extra_args_virt;
+ dma_addr_t extra_args_phys;
+ size_t alloc_size;
+};
+
+static u64 qcom_smccc_convention = -1;
+static DEFINE_MUTEX(qcom_scm_lock);
+
+#define QCOM_SCM_EBUSY_WAIT_MS 30
+#define QCOM_SCM_EBUSY_MAX_RETRY 20
+
+#define N_EXT_QCOM_SCM_ARGS 7
+#define FIRST_EXT_ARG_IDX 3
+#define N_REGISTER_ARGS (MAX_QCOM_SCM_ARGS - N_EXT_QCOM_SCM_ARGS + 1)
+
+/**
+ * qcom_scm_call() - Invoke a syscall in the secure world
+ * @svc_id: service identifier
+ * @cmd_id: command identifier
+ * @fn_id: The function ID for this syscall
+ * @desc: Descriptor structure containing arguments and return values
+ *
+ * Sends a command to the SCM and waits for the command to finish processing.
+ * This should *only* be called in pre-emptible context.
+ *
+*/
+static int qcom_scm_call(u32 svc_id, u32 cmd_id, struct qcom_scm_desc *desc)
+{
+ int arglen = desc->arginfo & 0xf;
+ int ret, retry_count = 0, i;
+ u32 fn_id = QCOM_SCM_FNID(svc_id, cmd_id);
+ u64 cmd, x5 = desc->args[FIRST_EXT_ARG_IDX];
+
+ if (unlikely(arglen > N_REGISTER_ARGS)) {
+ desc->alloc_size = N_EXT_QCOM_SCM_ARGS * sizeof(u64);
+ desc->extra_args_virt =
+ qcom_scm_alloc_buffer(desc->alloc_size,
+ &desc->extra_args_phys,
+ GFP_KERNEL);
+ if (!desc->extra_args_virt)
+ return qcom_scm_remap_error(-ENOMEM);
+
+ if (qcom_smccc_convention == ARM_SMCCC_SMC_32) {
+ u32 *args = desc->extra_args_virt;
+
+ for (i = 0; i < N_EXT_QCOM_SCM_ARGS; i++)
+ args[i] = desc->args[i + FIRST_EXT_ARG_IDX];
+ } else {
+ u64 *args = desc->extra_args_virt;
+
+ for (i = 0; i < N_EXT_QCOM_SCM_ARGS; i++)
+ args[i] = desc->args[i + FIRST_EXT_ARG_IDX];
+ }
+
+ x5 = desc->extra_args_phys;
+ }
+
+ do {
+ mutex_lock(&qcom_scm_lock);
+
+ cmd = ARM_SMCCC_CALL_VAL(ARM_SMCCC_STD_CALL,
+ qcom_smccc_convention,
+ ARM_SMCCC_OWNER_SIP, fn_id);
+
+ do {
+ arm_smccc_smc(cmd, arglen, desc->args[0], desc->args[1],
+ desc->args[2], x5, 0, 0, &desc->res);
+ } while (desc->res.a0 == QCOM_SCM_INTERRUPTED);
+
+ mutex_unlock(&qcom_scm_lock);
+
+ if (desc->res.a0 == QCOM_SCM_V2_EBUSY) {
+ if (retry_count++ > QCOM_SCM_EBUSY_MAX_RETRY)
+ break;
+ msleep(QCOM_SCM_EBUSY_WAIT_MS);
+ }
+ } while (desc->res.a0 == QCOM_SCM_V2_EBUSY);
+
+ if (desc->extra_args_virt)
+ qcom_scm_free_buffer(desc->alloc_size, desc->extra_args_virt,
+ desc->extra_args_phys);
+
+ if (desc->res.a0 < 0)
+ return qcom_scm_remap_error(ret);
+
+ return 0;
+}
/**
* qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
@@ -50,14 +186,68 @@ int __qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
*/
void __qcom_scm_cpu_power_down(u32 flags)
{
+ return;
}
int __qcom_scm_is_call_available(u32 svc_id, u32 cmd_id)
{
- return -ENOTSUPP;
+ int ret;
+ struct qcom_scm_desc desc = {0};
+
+ desc.arginfo = QCOM_SCM_ARGS(1);
+ desc.args[0] = QCOM_SCM_FNID(svc_id, cmd_id) |
+ (ARM_SMCCC_OWNER_SIP << ARM_SMCCC_OWNER_SHIFT);
+
+ ret = qcom_scm_call(QCOM_SCM_SVC_INFO, QCOM_IS_CALL_AVAIL_CMD,
+ &desc);
+
+ if (ret)
+ return ret;
+
+ return desc.res.a1;
}
int __qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt, u32 *resp)
{
- return -ENOTSUPP;
+ int ret;
+ struct qcom_scm_desc desc = {0};
+
+ if (req_cnt > QCOM_SCM_HDCP_MAX_REQ_CNT)
+ return -ERANGE;
+
+ desc.args[0] = req[0].addr;
+ desc.args[1] = req[0].val;
+ desc.args[2] = req[1].addr;
+ desc.args[3] = req[1].val;
+ desc.args[4] = req[2].addr;
+ desc.args[5] = req[2].val;
+ desc.args[6] = req[3].addr;
+ desc.args[7] = req[3].val;
+ desc.args[8] = req[4].addr;
+ desc.args[9] = req[4].val;
+ desc.arginfo = QCOM_SCM_ARGS(10);
+
+ ret = qcom_scm_call(QCOM_SCM_SVC_HDCP, QCOM_SCM_CMD_HDCP, &desc);
+ *resp = desc.res.a1;
+
+ return ret;
+}
+
+void __qcom_scm_init(void)
+{
+ u64 cmd;
+ struct arm_smccc_res res;
+ u32 function = QCOM_SCM_FNID(QCOM_SCM_SVC_INFO, QCOM_IS_CALL_AVAIL_CMD);
+
+ /* First try a SMC64 call */
+ cmd = ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_64,
+ ARM_SMCCC_OWNER_SIP, function);
+
+ arm_smccc_smc(cmd, QCOM_SCM_ARGS(1), cmd & (~BIT(ARM_SMCCC_TYPE_SHIFT)),
+ 0, 0, 0, 0, 0, &res);
+
+ if (!res.a0 && res.a1)
+ qcom_smccc_convention = ARM_SMCCC_SMC_64;
+ else
+ qcom_smccc_convention = ARM_SMCCC_SMC_32;
}
diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index 8e1eeb8..7d7b12b 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -166,6 +166,11 @@ bool qcom_scm_is_available(void)
}
EXPORT_SYMBOL(qcom_scm_is_available);
+static void qcom_scm_init(void)
+{
+ __qcom_scm_init();
+}
+
static int qcom_scm_probe(struct platform_device *pdev)
{
struct qcom_scm *scm;
@@ -208,6 +213,8 @@ static int qcom_scm_probe(struct platform_device *pdev)
__scm = scm;
__scm->dev = &pdev->dev;
+ qcom_scm_init();
+
return 0;
}
diff --git a/drivers/firmware/qcom_scm.h b/drivers/firmware/qcom_scm.h
index 7dcc733..d3f1f0a 100644
--- a/drivers/firmware/qcom_scm.h
+++ b/drivers/firmware/qcom_scm.h
@@ -36,7 +36,9 @@ extern int __qcom_scm_is_call_available(u32 svc_id, u32 cmd_id);
extern int __qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt,
u32 *resp);
+extern void __qcom_scm_init(void);
/* common error codes */
+#define QCOM_SCM_V2_EBUSY -12
#define QCOM_SCM_ENOMEM -5
#define QCOM_SCM_EOPNOTSUPP -4
#define QCOM_SCM_EINVAL_ADDR -3
@@ -56,6 +58,8 @@ static inline int qcom_scm_remap_error(int err)
return -EOPNOTSUPP;
case QCOM_SCM_ENOMEM:
return -ENOMEM;
+ case QCOM_SCM_V2_EBUSY:
+ return err;
}
return -EINVAL;
}
--
1.9.1
More information about the linux-arm-kernel
mailing list